docs: def serialize_me(self, account_id, region, next_token=None):
          """Dumps the proper JSON for the schema.
  
          :param account_id:
          :param region:
          :param next_token:
          :return:
          """
          payload = {
              'account_id': account_id,
              'region': region
          }
  
          if next_token:
              payload['next_token'] = next_token
  
          return self.dumps(payload).data